1. Field of the Invention
The present application is directed to a switching network for receiving and transmitting data packets having both frames and messages which utilizes a ring for messages and an associated crossbar switch for frames.
2. Description of the Related Art
In a switching network, all receiving channels (or ports) route data to a switching fabric. The switching fabric sends the data to a specific destination port. The data is normally in the form of data packets either of uniform or variable length. A data packet may include both frames which consist of relatively long strings of data bytes for example 40 to 64 bytes and larger, and messages which consist of small entities of, for example 4, 8, or 12 bytes. Such small entity messages might include formats of broadcast flow control, back pressure/feed forward messages, linked table configuration, write or read formats and other similar formats. Input ports are connected to output ports by a well known crossbar connection matrix. Such crossbar matrices typically reside on a die where there may be 64 ports and each port has a data bus of 16 signal lines. Thus, with a total of 2,048 signal lines, the crossbar switches are silicon resource intensive. In other words, to efficiently utilize this silicon resource (that is the silicon die on which the crossbar switch is integrated), it is very inefficient to transmit small entity messages (that is 4, 8, or 12 bytes, for example, as discussed above) through the crossbar switch. It is more efficient, rather, to transmit frame size packet portions which range from 40 to 64 bytes and greater.
Ring networks have also been suggested for data transfer. See IEEE 802.5 standard. However, this is used in a computer network where a computer must first catch a token and then attach a “message” to it.